Using stocks, it is easy to find graphs that show that
different representations of similar data can be used to illustrate
conflicting viewpoints.
I did this with Microsoft (MSFT). Using the web page
http://finance.yahoo.com/q?s=msft&d=c&k=c4
I changed the range to choose two different time frames that
showed conflicting information.

This first graph is
a stock performance graph of MSFT from January 2000 until September 27, 2002.
It shows MSFT decreasing from 120 to 46.
The top part of the graph shows the price of the stock,
while the bottom shows the volume or number of shares bought or sold each
day.
While there were fluctuations in the stock value,
this graph shows that MSFT decreases with time.

On the other hand, the following
is a stock performance graph of MSFT
from when the data for MSFT was first available (in 1986)
until September 27, 2002.
This graph shows that
MSFT started at about 0 and finished at 50.
This graph shows MSFT increasing over time.

We have shown that
different representations of similar data can be used to illustrate
conflicting viewpoints. Using the first graph, we see that
MSFT decreased in value over time, while the second
graph shows a different story of MSFT increasing in value over time.
When looking at data, both longterm and shortterm viewpoints must
be considered for an accurate representation.